Ernest B. Chang, OD
- Medicare patients, 2024
- 322
- Part D claims, 2024
- 36
- MIPS score, 2024
- 90
- Hospital affiliations
- 1
- Industry payments
- $120
- Practice address
- 2660 W Covell Blvd, Davis, CA 95616
- Practice phone
- Call (530) 747-3000
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Regents of the University of California
Davis, California
Find Ernest Chang's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Ernest B. Chang is an optometrist in Davis, California
Ernest Chang practices at Regents of the University of California in Davis, California.
Ernest Chang's NPI, 1235786898, was assigned on August 19, 2019. Ernest Chang graduated from Pacific University - College of Optometry in 2019. Ernest Chang holds California license 34341.
- NPI
- 1235786898NPI Registry (opens in a new tab)
- Medicare PAC ID
- 9436480597
- NPI enumeration date
- August 19, 2019
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (530) 747-3000
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 33
- Medical school graduation
- 2019
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Practice Data; and Doctors and Clinicians National Downloadable File (CMS)
Ernest B. Chang practices at Regents of the University of California in Davis, California
Ernest Chang's primary practice is Regents of the University of California, at 2660 W Covell Blvd, Davis, CA 95616 in Yolo County. The practice phone is (530) 747-3000.
- Regents of the University of California2660 W Covell Blvd, Davis, CA 95616 · Yolo CountyPhone(530) 747-3000
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Ernest B. Chang is affiliated with 4 sites of care and 2 medical groups
Ernest Chang's primary practice is Regents of the University of California in Davis, California. Ernest Chang is also affiliated with UC Davis Medical Center. The medical group on file is UC Davis Medical Group. Dmand AI also links Ernest Chang to 2 more group practices and clinics and 1 medical group, each named with a free account.
Sources: NPPES NPI Registry (CMS); Dmand AI Practice Data; and Dmand AI Affiliation Data
Dmand AI tracks the EHR system at Ernest B. Chang's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Ernest Chang practices, 3 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Regents of the University of California | Available with a free account |
| +3 more sites and 1 medical group | Available with a free account |
Source: Dmand AI Technology Install Data
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Ernest B. Chang is one of 7,206 optometrists in California
Optometrist is Ernest Chang's primary specialty in the NPI Registry, under taxonomy code 152W00000X. Ernest Chang is licensed in California.
Specialties and state licenses
- Optometrist, CaliforniaPrimary
Optometrists near Ernest Chang
Counts of optometrists with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Ernest B. Chang treated 322 Medicare patients in 2024, average age 75
CMS counts 322 Medicare patients who saw Ernest Chang in 2024. The largest group is 75 to 84, with 128 patients. 70% of them have high blood pressure, and 66% have high cholesterol. 23% are also on Medicaid. Their average risk score is 1.35, where 1.00 is the Medicare average.
Across all payers, Dmand AI patient panel data puts Ernest Chang's median patient age at 68, with 60% women.
Ernest Chang's Medicare patients by age, 2024
Ernest Chang's Medicare patients by sex, 2024
- Women20463%
- Men11837%
Chronic conditions among Ernest Chang's Medicare patients, 2024
- High blood pressure70%
- High cholesterol66%
- Arthritis51%
- Diabetes40%
- Mood disorders26%
- Depression23%
- Chronic kidney disease22%
- Ischemic heart disease22%
Share of Medicare patients with each condition. A patient can have several.
Ernest Chang's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 68
Patient panel by sex, all payers
- Women60%
- Men40%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Ernest B. Chang wrote 36 Medicare Part D claims in 2024
In 2024, Ernest Chang wrote 36 Medicare Part D claims for 22 patients. 53% of them were for generic drugs.
Ernest Chang's Part D claims by kind of drug, 2024
- Generic19 claims53%
- Brand-name17 claims47%
Source: Medicare Part D Prescribers - by Provider (CMS), 2024 data
Ernest B. Chang scored 90 out of 100 in Medicare's MIPS program for 2024
CMS publishes a Merit-based Incentive Payment System (MIPS) score of 90 out of 100 for Ernest Chang for performance year 2024, reported as part of a group. Ernest Chang accepts Medicare assignment, so Medicare's approved amount is taken as full payment.
- Accepts Medicare assignment
- Yes
Ernest Chang's MIPS scores, performance year 2024
- 90of 100Final score
- 86.2of 100Quality
- 100of 100Promoting Interoperability
- 40of 100Improvement Activities
- 78of 100Cost
Each score is out of 100. The final score weighs the categories CMS scored for this clinician.
Sources: Doctors and Clinicians National Downloadable File (CMS); and Clinician Public Reporting: Overall MIPS Performance (CMS), 2024 data, released September 10, 2026
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Ernest B. Chang received $120 in industry payments in 2025
CMS Open Payments shows 1 general payment to Ernest Chang from 1 drug or device company in 2025. Food and beverage make up the largest share, 100% of the total. Dompe US, Inc. paid the most, $120.
Companies that paid Ernest Chang the most, 2025 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Ernest B. Chang graduated from Pacific University - College of Optometry
Ernest Chang graduated from Pacific University - College of Optometry in 2019.
- Medical school
Source: Dmand AI Professional Profile Data
Sources for Ernest B. Chang's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Primary practice, affiliations and health system | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice DataDmand AI Affiliation Data |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| Part D prescribing | Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab)Clinician Public Reporting: Overall MIPS Performance (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Ernest B. Chang
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Ernest B. Chang's NPI number?
Ernest B. Chang's NPI number is 1235786898. It was assigned on August 19, 2019, and it is active in the NPI Registry.
What does Ernest B. Chang specialize in?
Ernest B. Chang is an optometrist in Davis, California. The primary specialty in the NPI Registry is Optometrist (taxonomy code 152W00000X).
Where does Ernest B. Chang practice?
Ernest Chang practices at 2660 W Covell Blvd, Davis, CA 95616. Ernest Chang's primary practice is Regents of the University of California in Davis, California. Dmand AI also links Ernest Chang to 2 group practices and clinics and 1 medical group.
What is Ernest B. Chang's office phone number?
The practice phone on file for Ernest Chang is (530) 747-3000.
What is Ernest B. Chang's medical license number?
Ernest Chang holds California license 34341.
Which hospitals is Ernest B. Chang affiliated with?
Ernest Chang is affiliated with UC Davis Medical Center.
What medical group is Ernest B. Chang part of?
Ernest Chang is linked to UC Davis Medical Group. Dmand AI links Ernest Chang to 1 more medical group.
Does Ernest B. Chang accept Medicare?
Yes. CMS lists Ernest Chang as accepting Medicare assignment.
What is Ernest B. Chang's MIPS score?
Ernest Chang's MIPS final score for performance year 2024 is 90 out of 100, reported as part of a group.
How many Medicare patients does Ernest B. Chang see?
CMS counts 322 Medicare patients who saw Ernest Chang in 2024, with an average age of 75.
Show 3 more questionsShow fewer questions
Where did Ernest B. Chang go to medical school?
Ernest Chang graduated from Pacific University - College of Optometry in 2019.
Has Ernest B. Chang received payments from drug or device companies?
CMS Open Payments shows $120 in general payments to Ernest Chang from 1 company from 2025 to 2025. The largest total came from Dompe US, Inc.
How long has Ernest B. Chang been practicing?
Ernest Chang graduated from medical school in 2019, 7 years ago.
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